"Lose Yourself," the fierce and furious No. 1 single that leads off the soundtrack to Eminem's debut movie, is as good as anything on this year's The Eminem Show. Just as gripping is the title track, which in six powerful minutes serves as a musical Cliff Notes to the film. Both songs, however, are miles ahead of the rest of this hardcore disc. With so-so showings by Nas and Macy Gray (on one of two nonrap tracks), 8 Mile, like most soundtracks, stretches itself too thin. Even Eminem's other three contributions (one more solo cut, two collaborations with lesser labelmates) are relatively routine. But it's good to hear pioneer emcee Rakim, who on "R.A.K.I.M." proves that he could still battle anyone.